Electric switch



w. s. GARLAND ELECTRIC SWITCH Filed July 28, 1959 W 6' Gual an d www3:

Patented Aug. 19, 1941 UNVIED STATES PATENT OFFICE ELECTRIC SWITCH'Walter S. Garland, Oakland', Calif., assignor to Ruby R. Garland,Oakland, Calif.

Application July 28, 1939, SerlaI'No. 287,177

1 Claim. (Cl. 20D- 82)l This invention relates to an improved electricswitch and seeks, among other objects, to provide a device of thischaracter which is adapted for use with internal combustion engines andwhich will operate for indicating below normal operating efficiency ofthe engine.

Another object ofthe invention is to provide an electric switch havingla beacon light connected therewith which will be illuminated uponfailure of the vacuum in the manifold of the engine to retain a normaloperating efficiency, so that an operator may be warned of suchsubnormal operating efficiency of the motor to the end that correctivemeasures' may be taken.

A further object of the invention is to provide an electric switch, theuse of which will permit the operator of the motor to secure greaterfuel economy and engine efliciency.

A further object of the invention is to provide a switch of thischaracter which will be of simple construction and which may beinstalled with the utmost'facility'.

Other and incidental objects of the invention not mentioned hereinbeforewill become apparent during the course of the following description.

Reference is now had to the accompanying drawing, wherein:

Figure 1 is a perspective view, partly in diagram, showing my improvedelectric switch as it would appear installed on an engine manifold,

Referring now more particularly to the drawing, wherein like numerals ofreference will be seen to designate like parts throughout the variousviews, the numeral I indicates a motor of the internal combustion typewhich may be of any suitable design. The motor has a conventional intakemanifold 2 which is provided with a main intake pipe 3.

In carrying my invention into effect, I provide a switch member 4 whichincludes a valve or cylinder 5 having a reduced portion 6 at one end.The reduced portion 6 defines a shoulder 6a. The reduced portion 6 isfurther reduced to define an externally threaded neck I which is to bescrewed into the pipe 3 near its upper end, or in any other convenientlocation. The cylinder 5 is provided throughout the major portion of itslength with a bore 9. The bore 9 is reduced in diameter near its innerend to define a springreceiving portion I0. A passage II, disposedaxially of the neck 1, leads from the inner end of the springreceivingportion I0 to the interior off the manifold, said passage defining aspring base I2'.

Snugly butV slidably mounted in the bore 9 is a` piston I3; 'I'he pistonis provided with an end portion' I4 and is' hollow throughout itslength. The piston is normally urged outwardly, that is to say, awayfrom the manifold, by a coiled spring I5 which is mounted in the boreand spring-receivingV portion.

In order to close the outer end of the cylinder and the' bore, I providean end wall I6 which is ofv insulating material. The end wall I6 isfitted intothe end of the cylinder and engages against a shoulder IIdefined at the outer end of the bore 9"' by said bore and a flange I8.The flange I8 is upset at diametrically opposed portions of its freeedge for holding the wall I6 in place. Spanner openings I 9 are providedfor the outer surface of the wall IS so that ready engagement by aSpanner wrench will be permitted when it is desired to remove the wallI6. The end wall I6 has mounted therein a contact bolt 20 which has acontact head 2I thereon, the contact head 2| being adapted forengagement by the end portion I4 of the piston I3. Screwed on thecontact bolt 2|) is a lock nut 22, which lock nut, of course, securesthe bolt 20 in position on the wall I6. A securing nut 23 is screwed onthe bolt 20 and provides means whereby a wire may be effectivelyconnected to the switch member.

Formed in the cylinder 5 of the member 4 is a vent opening 24 which willpermit escape of air confined between the outer portion I4 of the pistonand the inner surface of the end wall I6. The opening 24 may be locatedin the wall I6 if desired.

After the device has been installed, as shown in Figures 1 and 2, aconductor 25 has one of its ends connected to the contact bolt 20. Theother end is connected to one terminal of an ignition switch 8, theother terminal of said switch 8 being connected to a warning device,such as the signal light 26. The other terminal of the warning device 26is connected to one terminal of the battery 21. The other terminal ofthe battery is connected to the frame of the vehicle, as is the cylinder5 of the switch member 4. If desired, a single pole switch may beinterposed in the wiring for cutting the device in and out of thecircuit. Of course, in actual use, the device will be connected to theignition switch of the motor Vehicle or motor so that said device willnot become operative until the switch is turned on. When the switch hasbeen turned to the on position, the

light 26 will burn. When the motor is started, however, vacuum createdin the intake manifold by the movement of the cylinders will cause thepiston I 3 to be drawn in the cylinder 5, away from the end wall I6. Theend portion I4 will thus be kept out of engagement with the contact head2 I The circuit to the warning device 26 will thus be opened. Thiscondition will prevail so long as the vacuum in the manifold ismaintained at a proper level. In the event that the vacuum in themanifold drops to a sub-normal position, such as would be caused bystalling of the motor, or poor vacuum condition, the spring I5 will urgethe piston in the cylinder until the end portion I4 engages the head 2|.The circuit will then be completed to the warning device 26 and the samewill be illuminated, or sounded, as the case may be, for indicating tothe operator that the Vacuum condition is sub-normal or that the motorhas stalled. Fuel Waste may be reduced to a minimum. It should beunderstood that the tension of the spring will be predetermined so thatsaid spring will operate when a predetermined vacuum condition e'xists.It will now be understood that, by

the use or my improved electric switch, it will be possible for anoperator to maintain a motor running at maximum efliciency.

Referring now to the modification of the in vention as shown in Figure3, the numeral 28 indicates a portion of a manifold. A cylinder 29 has aneck 3G which is screwed into the manifold. A shoulder 28@ limits inwardmovement of the cylinder. The cylinder 29 is provided with an enlargedportion 3i which is externally threaded to receive an enlarged circularCap 32. Confined between the cap and the portion 3| is a diaphragm 33 onwhich is mounted a contact 34, said contact being mounted on a. disk 35.Mounted in the cap 32 is a plug 36 of insulating material, and securedto the plug is a contact bolt 31. A contact head 38 is carried on theContact bolt,

and said contact bolt is held in place by a nut 39. A securing nut 4|]provides means for securing a conductor to the device.

Mounted in the cylinder 29 is a spring 4I. A bore 42 leads from thecylinder 29 to the interior of the manifold 2B. In operation, a suitablevacuum condition in the manifold will result in the retention, by saidvacuum, of the diaphragm 33, away from the cap 32. The contact 34 willbe retained away from the head 38 and the electric circuit will bebroken. Should the condition of vacuum fall to sub-normal, the spring 4Iwill overpower the vacuum condition and will urge the diaphragm towardthe cap 32 so that the contact 34 Will engage the head 38 for closingthe electric circuit. The wiring in the modified form is identical withthat of the preferred form.

Having thus described the invention, what is claimed as new is:

4in electric switch including a switch member having a sleeve formedwith a bore, said bore being reduced to define a shoulder and a springreceiving portion, a piston slidable in the bore and having a closedouter end portion and an opcn inner end portion, an end wall ofinsulating material closing the bore at its outer end, said bore havingan opening defining a vent, a contact bolt carried on the end wall andhaving a contact head within the bore, and a spring carried in thespring receiving portion and extending within the piston and normallyurging the end portion of the piston into engagement with the contactbolt, said piston being shiftable against the tension of the spring fordisengaging the end portion from the contact head by suction from anintake manifold, said shoulder engaging the open inner end cf the pistonand limiting inward movement thereof, said piston dening a guide forsaid spring and said vent admitting air to the bore for allowingmovement of the piston therein.

WALTER S. GARLAND.

